Techniques for detecting a steered angle of an outboard engine by use of a rotational angle sensor have been known, one example of which is disclosed in Japanese Patent Application Laid-Open Publication No. 2004-230949 (JP 2004.230949 A).
FIG. 8 hereof illustrates the technique disclosed in JP 2004-230949 A. An outboard engine unit 100, which is mounted to a hull or body 101 of a boat via a stern bracket 102, has an outboard engine body 103 rotatably mounted to the stern bracket 102 via a swivel shaft 104. The outboard engine body 103 is steered about a central axis 106 of the swivel shaft 104 by a steerperson moving a tiller handle 105 horizontally leftward or rightward (i.e., toward or away from a person viewing the figure). A steered angle of the outboard engine body 103 is detected via a pivotal angle sensor 107 provided on the swivel shaft 104.
The outboard engine body 103 is sometimes steered through 50 degrees or more at the time of leftward or rightward steering. Thus, the pivotal angle sensor 107 is required to have a capability of detecting pivot angles of 100 degrees or more corresponding to a sum of such possible leftward and rightward steered angles.
However, the pivotal angle sensor 107 capable of detecting pivot angles of 100 degrees or more is expensive, increasing overall cost of the outboard engine unit 100. Thus, there has been a need for an outboard engine unit which is provided with an inexpensive steered angle detection mechanism and yet can achieve satisfactory performance.